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A221290 as a triangular array

1
11
241
416121
75292371
122006735561141
217925912910733323511
373080482981729041239581999610811
651216439684628900174983598168630411997233291
11447827324052749684593

A221290 as a square array

1124712213765114
14165220079230801216447827
112926735912482983968463240527
1375569107172904289001749684593
111433321239584983598
1351199961686304
11081119972
13329
1
1124712213765114
14165220079230801216447827
112926735912482983968463240527
1375569107172904289001749684593
111433321239584983598
1351199961686304
11081119972
13329
1